Visual motor analyzer



w. L. ems-row 2,211,196 VISUAL MOTOR ANALYZER Aug. 13, 1940.

Filed Nov. 30, 1937 INVENTOR. M/ILL m M L. .BR/STOVV.

l1 TTORNEY Patented Aug. 13, 1940 UNITED STATES PATENT OFFICE VISUAL MOTOR ANALYZER William L. Bristow, San Francisco, Calif. Application November 30, 1937, Serial No. 177,294 2 Claims. (01. 73-51) The invention generally relates to indicators and more particularly relates to a device responsive to the'pressure of gases emitted from the exhaust pipe of an internal combustion engine 5 to the end that engine conditions are readily analyzed.

It is probably well known that the pressure of the exhaust gases from an internal combustion engine is substantially regular in pulsations when conditions in the engine are such that the engine is operating at its maximum efliciency. Moreover, that whenever a condition exists in the engine that causes it to operate inefficiently or below par, such deleterious condition is reflected immediately by variations in pressures of the exhaust gases. Heretofore, the average skilled automotive mechanic has depended upon audible indications of the varying pressure of the exhaust gases to lead him to the engine trouble. This type of indication is not dependable due to many disturbing conditions such as noises in and around the garage as well as the fact that at various engine speeds there are decided variations in the audibility of the emitted exhaust gases ranging from a relatively loud sound to one that is barely audible. The present invention avoids all such difficulties and affords a visible means of indicating variations in the pressure of the exhaust gases while not entirely eliminating the audible indication of the past.

It is an important object of the present invention to provide a relatively simple, portable motor analyzer which is responsive to the pressure of the exhaust gases emitted from the exhaust pipe of an internal combustion engine. Another object of my invention is to provide a device of the aforementioned character which is readily removably connected in operated position in communication with the exhaust pipe of an engine.

A still further object of the invention is to provide a motor analyzer of the character indicated which is inexpensively manufactured and easy to maintain.

Other objects of the invention, together with some of the advantageous features thereof, will appear from the following description of a preferred embodiment of my invention which is illustrated in the accompanying drawing.

It is to be understood that while I have illustrated a preferred embodiment of my invention in the annexed drawing, I am not to be limited to the precise embodiment shown, as my invention, as defined in the appended claims, can be 55 embodied in a plurality and variety of forms.

Referring to the drawing:

Figure 1 is a diagrammatic View, partly in sectional elevation, illustrating a preferred embodiment of the invention in position assembled on the exhaust pipe of an internal combustion engine.

Figure 2 is a plan view of the top of the preferred embodiment of the invention shown in Figure 1.

Figures 3, 4 and 5 are elevational views of different types of valves, pistons or plungers that may be incorporated in the embodiment of the invention shown in Figure 1.

In its preferred form, the visual motor analyzer of my invention preferably comprises a hollow body having an opening at each end thereof, a piston or plunger movably mounted in said body, together with means establishing communication between the exhaust pipe of an internal combustion engine and the interior of said body below said valve.

In accordance with my invention, I provide a hollow tapered body II which preferably is tapered from a wide or flaring top to a relatively narrow bottom, as shown, and which preferably is fabricated of metal, although any other suitable material, such as a phenolic condensate, can be used, as desired. The body H is formed with an opening H1 at one end thereof and an open ing l2 at the other end thereof so that gases entering through opening ill may pass through the body and be emitted from opening 62. Loosely mounted in the tapered body H is a piston or plunger l3, the stem IA of which extends beyond the opening l2 of the body. In the embodiment illustrated, one end of the body it is closed with a removable cap or top I6 having openings l2 therein and having a web it spanning the same with an opening 15 in the web for passing the stem M of the piston l3 and serving as a guide therefor. If desired, the cap or top it can be formed integral with the body H. The piston or plunger i3 is adapted to cover the opening Ii] in theother end of the body I i when the piston is in its lowered position, it being understood that the device preferably is operable in a vertical position as indicated in Figure l of the drawing. The lower end of the tapered body I i may be provided with a reducer ll for receiving a tube or conduit it] which preferably is flexible, as shown.

' The flexible tubing or conduit !8 establishes communication between the interior of body H below the piston or plunger 13 and the exhaust pipe of an internal combustion engine. While an internal combustion engine per se is no part of my invention, I have shown certain parts of such an engine bearing upon or relating to the present invention, such as the exhaust manifold is of the engine which communicates with an exhaust pipe 2| detachably secured to the manifold and in which the conventional exhaust mufiler 20 is installed which communicates with the muffler tail pipe 22 as shown, and I preferably connect the flexible tube or conduit is, by means of a suitable adapter such as a tapered bored plug 23, to the end of the muiiler tail pipe 22. As is obvious, the tubing i8 is readily removed and as readily attached to tail pipe 22 thus alfording a qu ck means of establishing communication between the body l E and the exhaust pipe of the engine.

The device of my invention normally is connected in operative position as illustrated in Figure 1 of the drawing with the body H supported vertically, as shown. Any suitable supporting means may be employed for affording vertical disposition of the body. With the engine in operation, exhaust gases are conducted unrestrictedly from the muiiier tail pipe 22 of the vehicle to within body il below the piston or plunger l3. Assuming that the engine is operating at maximum efi'iciency at idling speed, the pressure of the exhaust gases, which is a pulsating pressure at this speed, will effect a rise of the piston [3 to cause the stem I4 to protrude somewhat farther from the cap 46 than when the piston is at the bottom of the body. Due to the pulsating character of the exhaust gas pressure at idling speeds, the piston 13 will flutter or reciprocate but within narrow ranges. If the engine is accelerated, and maximum efficiency of operation still obtains, the piston [3 will rise somewhat higher within the body I I than when the engine is idling and will continue to flutter but within smaller ranges of fluctuations than formerly or at idling speeds. In Figure l of the drawing, the reference letter A is indicative of the position about which piston [3 will flutter with the engine operating at an idling speed while reference letter B indicates the position about which the piston 13 will flutter with the engine running at slightly higher than idling speed. As stated above, at increased speeds of the engine the piston I3 will rise higher in body H and fluctuate within narrow limits at such higher position. It is to be observed that the exhaust gases are emitted to the atmosphere from body H through the top thereof as piston I 3 is raised by the pressure of such gases, all as indicated by the arrows in Figure l of the drawing.

In the event that the internal combustion engine, connection with which the device of my invention is used, is operating below par or lower than its maximum efficiency, that fact will be immediately reflected by variations in exhaust gas pressure and will be translated for visual indication to the piston or plunger l3. Instead of constantly fluttering about a definite position, as at A or B, the movement of piston l3 will be irregular in that it will flutter about a definite position for a limited period and then recurrently and rapidly rise or fall to a high or low position, as indicated by reference letters C and D, but returning to its former definite position about which it will flutter for a while and repeat the foregoing irregular cyclic movement until the deleterious condition in the engine is corrected. Upon correction of the trouble, the piston [3 will resume its regular fluttering action about a definite position depending upon the speed at which the engine is driven.

I have applied the device of my invention to various makes and models of automobiles in which the engines have been found faulty. I have found that various faulty conditions in an engine are reflected in or translated to the plunger or piston l3 so that the piston l3 responds in various ways. For example, if the engine in connection with which my device is used has a defective or shorted spark plug, the plunger or piston l3 will flutter about a definite position, as at A, if at engine idling speed, for a limited period and then drop rapidly to the position indicated at D and then back to position A about which it will flutter again for an interval of time and repeat its drop to position D. This recurrent movement of the piston or plunger 13 continues until the faulty spark plug is repaired or a new plug substituted therefor. After the condition is corrected and with the engine operating at engine speed, the eificiency of the engine is again indicated by the movement of the plunger or piston 53. If the piston flutters within a narrow range about a definite position, as at A, and without deviation therefrom, the motor will be operating at substantially maximum efiiciency. In short, marked deviations of the plunger or piston l3 from a definite position in the body ll about which the piston flutters in response to the pulsating character of the emitted exhaust gases, indicates motor trouble while regular fluctuation of the piston I3 about a definite position, depending upon the R. P. M. of the engine, indicates that the engine is in good condition.

The faulty or deleterious conditions of an internal combustion engine which will be reflected in the exhaust gas pressure and which will be translated to the piston l3 of my device include faulty ignition, such as improper timing, sticking valves or broken valves, varying compression in the different cylinders resulting from valve seatings or leaky piston rings, an advance spark or the carburetion of the combustible mixture. I have found that if the mixture of combustible gases is lean, the piston [3 will reciprocate within the body on a long and fast stroke, that is, a rapid varying between a, low and high position in the body whereas a rich mixture of the combustible gases will be reflected by a relatively slow, short stroke of the plunger l3. All of the tests that I have made have been in connection with the conventional internal combustion engine of the Otto or four cycle type and it has been found that any variation in the exhaust pressure is immediately visible in the irregular reciprocating action of the plunger i3 loosely mounted in the body H.

Figures 3, 4 and 5, inclusive, illustrate different types of pistons or plungers that may be used in lieu of the fiat base piston I 3 shown in Figure 1. These pistons or plungers may be convex or concave, as indicated, or a ball type, as shown in Figure 5, may be employed.

I claim:

1. An analyzer for use in observing the condition of a motor or the like, said analyzer comprising a hollow, tapered body, a cap detachably secured on said body; said cap having a central opening therein as well as additional openings therein establishing communication between the interior of said body and the atmosphere, a bottom on said body having an opening therein, a piston loosely mounted within said body and adapted to cover the opening in said bottom; said piston being of less diameter than the internal diameter of said body at its narrowest point to provide a definite clearance therebetween, a piston rod on said piston projecting through said central opening of said cap, and a flexible conduit detachably fitted to the opening in said bottom and adapted to establish communication between the exhaust pipe of a motor and the interior of said body and unrestrictedly to conduct to and indeterminateiy to conduct through said body exhaust gases of the motor for emission from the body to the atmosphere through said additional openings in said cap.

2. An analyzer for use in observing the condition of a motor, said analyzer comprising a hol- 10w, tapered body having a first opening at one end thereof and a second opening at the other end thereof, an apertured top on said body partially closing said second opening, a piston loosely mounted in said body and adapted to cover said first opening; said piston being of less diameter than the internal diameter of said body at its narrowest point to provide a definite clearance therebetween, a piston rod on said piston extending through said top beyond said second opening, and a flexible conduit connected to said body and. communicating With the interior of said body through said first opening below said piston; said conduit being adapted to establish communication between the exhaust pipe of a, motor and the interior of said body and unrestrictedly to conduct exhaust gases to said body for indeterminate passage therethrough and emission to 15 the atmosphere from said second opening.

WILLIAM L. BRISTOW. 

